[go: up one dir, main page]

US20030004349A1 - Work-up of the mother liquor obtained in the preparation of high-purity triethylenediamine - Google Patents

Work-up of the mother liquor obtained in the preparation of high-purity triethylenediamine Download PDF

Info

Publication number
US20030004349A1
US20030004349A1 US10/138,337 US13833702A US2003004349A1 US 20030004349 A1 US20030004349 A1 US 20030004349A1 US 13833702 A US13833702 A US 13833702A US 2003004349 A1 US2003004349 A1 US 2003004349A1
Authority
US
United States
Prior art keywords
teda
mother liquor
solvent
extractant
extraction
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
US10/138,337
Other versions
US7345173B2 (en
Inventor
Ortmund Lang
Bernd Rumpf
Matthias Frauenkron
Dirk Funhoff
Thomas Manderbach
Bernd Stein
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
BASF SE
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Assigned to BASF AKTIENGESELLSCHAFT reassignment BASF AKTIENGESELLSCHAFT ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: FRAUENKRON, MATTHIAS, FUNHOFF, DIRK, LANG, ORTMUND, MANDERBACH, THOMAS, RUMPF, BERND, STEIN, BERND
Publication of US20030004349A1 publication Critical patent/US20030004349A1/en
Assigned to BASF SE reassignment BASF SE CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). Assignors: BASF AKTIENGESELLSCHAFT
Application granted granted Critical
Publication of US7345173B2 publication Critical patent/US7345173B2/en
Adjusted expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D487/00—Heterocyclic compounds containing nitrogen atoms as the only ring hetero atoms in the condensed system, not provided for by groups C07D451/00 - C07D477/00
    • C07D487/02—Heterocyclic compounds containing nitrogen atoms as the only ring hetero atoms in the condensed system, not provided for by groups C07D451/00 - C07D477/00 in which the condensed system contains two hetero rings
    • C07D487/08—Bridged systems

Definitions

  • the present invention relates to a process for working-up mother liquor obtained in the preparation of triethylenediamine (TEDA) which has been subjected to a particular purification process.
  • This purification process comprises vaporizing TEDA, passing it in gaseous form into a liquid solvent and crystallizing the TEDA from the resulting solution.
  • the mother liquor obtained after this crystallization step is then worked-up according to the present invention.
  • TEDA is an important catalyst for the production of polyurethane foams.
  • TEDA is solid at room temperature.
  • Various methods are known for its preparation and purification, including the methods disclosed in the following publications:
  • TEDA is comparatively difficult to handle without deterioration of the quality, in particular in respect of color and color stability, odor and purity, occurring.
  • the application DE 101 00 943.7 of Jan. 10, 2001 by the Applicant describes a process for preparing a solution of pure TEDA, which comprises vaporizing TEDA from a mixture comprising a solvent or a diluent which has a boiling point at atmospheric pressure in the range from 175 to 250° C. and passing the gaseous TEDA into a liquid solvent. Subsequent crystallization of the TEDA from the resulting solution gives pure TEDA of high quality.
  • the first step of the process of the present invention comprises the reaction steps of the purification of TEDA as described in the applications DE 199 33 850.7, 199 62 455.0 and DE 101 00 943.7 by the Applicant.
  • the processes for purifying TEDA described in these applications are an integral part of the process of the present application and are hereby incorporated by reference. The processes will be briefly described again below.
  • organic solvents are suitable for this TEDA quench.
  • examples include aliphatic, cyclic or acyclic hydrocarbons, in particular cyclic and acylic, branched or unbranched alkanes or alkane mixtures, for example n-pentane, i-pentane, cyclopentane, hexane, cyclohexane, heptane, octane and petroleum ether, chlorinated aliphatic hydrocarbons, in particular chlorinated alkanes, for example dichloromethane, trichloromethane, dichloro ethers and trichloro ethers, aromatic hydrocarbons, for example benzene, toluene and xylenes, chlorinated aromatic hydrocarbons, for example chlorobenzene, alcohols, for example methanol, ethanol, ethylene glycol, 1,4-butanediol and polyether alcohols, in particular polyalkylene glycol
  • the solvent used for the TEDA quench is preferably an aliphatic hydrocarbon or a polyalkylene glycol, in particular a saturated cyclic or acyclic, aliphatic hydrocarbon having from 5 to 8 carbon atoms, for example pentane, hexane, cyclohexane or heptane, or dipropylene glycol.
  • the crystallization of the pure TEDA from the TEDA solution prepared according to the present invention can be carried out by methods known to those skilled in the art.
  • the TEDA crystals obtained by a subsequent, multistage or preferably single-stage crystallization are highly pure.
  • the gaseous TEDA is passed into the liquid solvent in a quenching apparatus, preferably a falling film condenser (thin film, trickle film or falling stream condenser) or in a nozzle apparatus.
  • the gaseous TEDA can be conveyed in cocurrent or in countercurrent to the liquid solvent. It is advantageous to pass the gaseous TEDA into the quenching apparatus from above. Also advantageous is the tangential introduction of the liquid solvent at the top of the falling film condenser or introduction of the liquid solvent through one or more nozzles to achieve complete wetting of the inner wall of the quenching apparatus.
  • the amount of solvent used is chosen according to practical considerations. In general, the amount used is such that, depending on the type of solvent, solutions having a TEDA content of from about 1 to 50% by weight, preferably from 20 to 40% by weight, are obtained.
  • the temperature in the TEDA quench is set to from 20 to 100° C., preferably from 30 to 60° C., by heating/cooling the solvent used and/or the quenching apparatus.
  • the absolute pressure in the TEDA quench is generally from 0.5 to 1.5 bar.
  • the TEDA is, as described in DE 101 00 943.7, vaporized from a mixture with a solvent or diluent
  • the solvent or diluent preferably has a boiling point at atmospheric pressure of from 180 to 250° C., in particular from 180 to 230° C., especially from 190 to 210° C.
  • Particularly useful solvents or diluents which may be present in the mixture from which the TEDA is vaporized are inert
  • polar aprotic solvents such as alkyl-2-pyrrolidones, for example N-methyl-2-pyrrolidone (NMP), 1-ethyl-2-pyrrolidone, 1,5-dimethyl-2-pyrrolidone, 1-isopropyl-2-pyrrolidone, ethers, for example diethylene glycol diethyl ether, triethylene glycol dimethyl ether and triethylene glycol diethyl ether, ketones, for example acetophenone and propiophenone, lactones, for example ⁇ -buyrolactone, sulfoxides, for example dimethyl sulfoxide, carboxylic esters, for example dimethyl fumarate, nitriles, for example benzonitrile, and ureas, for example 1,3-dimethylimidazolidin-2-one (DMEU) and tetramethylurea,
  • NMP N-methyl-2-pyrrolidone
  • 1-ethyl-2-pyrrolidone 1,5
  • cyclic or acyclic hydrocarbons in particular saturated cyclic or acyclic hydrocarbons, for example undecane, dodecane, cis-decalin and trans-decalin,
  • chlorinated aliphatic hydrocarbons for example 1-chlorooctane and 1,1-dichlorooctane,
  • aromatic hydrocarbons for example naphthalene, n-butylbenzene, phenol, cresol, nitrobenzene and nitrophenol,
  • chlorinated aromatic hydrocarbons for example 1,2-dichlorobenzene, benzyl chloride, 1,2,3,4-tetramethylbenzene and 1,2,3,5-tetramethylbenzene,
  • alcohols for example benzyl alcohol, 2-ethylhexanol, 1-octanol, i-decanol, 1,2-propanediol, 1,3-propanediol, ethylene glycol, diethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butanediol, 1,3-butanediol, 2,3-butanediol, 1,4-butanediol, neopentyl glycol, diethylene glycol monomethyl ether and dipropylene glycol,
  • primary, secondary and tertiary amines for example tri-n-butylamine, benzylamine, aniline, N-ethylaniline, N,N-dimethylaniline and N,N-diethylaniline,
  • N-alkylamides for example N-methylformamide and N-methylacetamide and mixtures thereof.
  • polar aprotic solvents or diluents having an E N T of from 0.1 to 0.6, in particular from 0.2 to 0.5, especially from 0.3 to 0.45.
  • Very particularly preferred solvents are NMP and ethylene glycol.
  • the solvent or diluent present in the mixture from which the TEDA is vaporized is preferably added to the crude or still contaminated TEDA after the synthesis of the TEDA.
  • the solvent or diluent can be used in a single pass or as a circulating solution after removal of the high boilers.
  • the amount of solvent or diluent used is chosen according to practical considerations. In general, the amount used is such that, depending on the type of solvent or diluent, solutions or mixtures having a TEDA content of from about 1 to 90% by weight, preferably from 40 to 70% by weight, are obtained.
  • the vaporization of the TEDA can be carried out by methods and under conditions with which those skilled in the art are familiar, e.g. in a distillation or rectification apparatus in which the TEDA is placed, optionally together with the solvent or diluent.
  • the gaseous TEDA is preferably obtained at the top or at a side offtake of a distillation column.
  • the gaseous TEDA in the process of the present invention generally has a purity of greater than 90% by weight, preferably greater than 95% by weight, in particular greater than 97% by weight.
  • the temperature of the mixture is set to ⁇ 230° C., preferably from 190 to 210° C., by selection of the solvent or diluent to be used, the TEDA content of the mixture and/or the pressure.
  • the absolute pressure is generally from 0.1 to 5 bar, preferably from 0.5 to 1.5 bar.
  • the time between when the gaseous TEDA used in the process of the present invention is obtained and the TEDA quench is advantageously ⁇ 10 seconds.
  • the TEDA to be purified can be obtained by known methods, e.g. by reaction of monoethanolamine, diethanolamine, triethanolamine, ethylenediamine, diethylenetriamine, triethylenetetramine, piperazine, N-(2-hydroxyethyl)piperazine, N,N′-bis(2-hydroxyethyl)piperazine, N-(2-aminoethyl)piperazine, N,N′-bis(2-aminoethyl)piperazine, morpholine, or mixtures thereof over a catalyst, for example metal pyrophosphates, metal phosphates, e.g.
  • the pressure is usually from 0.1 to 50 bar, in particular from 0.1 to 5 bar.
  • the reaction can optionally be carried out in the presence of an inert polar aprotic solvent such as an N-alkylpyrrolidone, for example N-methylpyrrolidone, dioxane, THF, a dialkylformamide, for example dimethylformamide, a dialkylacetamide, for example dimethylacetamide, or an inert polar protic solvent, for example water, and an inert carrier gas, for example N 2 or Ar.
  • an inert polar aprotic solvent such as an N-alkylpyrrolidone, for example N-methylpyrrolidone, dioxane, THF, a dialkylformamide, for example dimethylformamide, a dialkylacetamide, for example dimethylacetamide, or an inert polar protic solvent, for example water, and an inert carrier gas, for example N 2 or Ar.
  • the TEDA is subsequently crystallized from the mother liquor and separated off by solid/liquid separation.
  • the mother liquor obtained in this way is, according to the present invention, brought into intimate contact with an extractant in an extraction step. Mass transfer takes place in this step.
  • the extractant is selected so that the TEDA is taken up by it.
  • the by-products and decomposition products responsible for the reduction in the quality of the TEDA are likewise dissolved in the extractant.
  • the mother liquor is thereby freed of these by-products and decomposition products and can be returned to the process.
  • the solvent used as extractant advantageously has the following properties:
  • the extractant should have a large miscibility gap with the solvent used in the crystallization step; the mutual solubility of extractant and solvent should be ⁇ 10% by weight, preferably ⁇ 1% by weight.
  • TEDA should dissolve significantly better in the extractant than in the solvent which is used in the crystallization step.
  • the extractant and the solvent used in the crystallization step should have a sufficient density difference. This aids separation of the extract phase and the raffinate phase.
  • the density difference should preferably be >50 kg/m 3 , in particular>100 kg/m 3 .
  • Solvents which are preferred according to the present invention as extractants are water and water-miscible solvents such as lower alcohols or dihydric or polyhydric alcohols.
  • suitable alcohols include methanol, ethanol, n-propanol, i-propanol, ethylene glycol, polyethylene glycol and glycerol.
  • the alcohols can be used individually or as mixtures, optionally also in admixture with water.
  • the most preferred extractant is water.
  • the work-up according to the present invention of the mother liquor by means of an extractant can be carried out by the methods and under the conditions with which those skilled in the art are familiar, e.g. in an extraction apparatus into which the mother liquor is introduced continuously or batchwise, in each case together with the extractant.
  • the extraction according to the present invention reduces the amount of TEDA present in the mother liquor to values of ⁇ 10% by weight, preferably ⁇ 1% by weight, of the original value.
  • the extract phase after the extraction according to the present invention accordingly contains >90% by weight, preferably >99% by weight, of the TEDA originally present in the mother liquor.
  • solutions having a TEDA content of from about 1 to 40% by weight, preferably from 5 to 30% by weight, in particular 10-30% by weight, are obtained.
  • the extract phase may if appropriate be recycled after the extraction according to the present invention has been carried out and be reused for the extraction.
  • the degree of saturation of TEDA and by-products and intermediates in the extract phase will determine whether and how often the extract phase can be reused.
  • the degree of saturation depends greatly on the nature of the solvent used as extractant and on the solubility of TEDA and the by-products and intermediates in this solvent.
  • the extractant can also be taken from the process and worked up after a single extraction. This is done, in particular, when using water because of its ready availability.
  • the solvent used for the extraction can no longer take up TEDA and by-product and can no longer be recirculated.
  • This extract phase is then worked up and separated into the solvent used and TEDA, preferably by distillation.
  • the solvent is then reused as extractant.
  • TEDA of differing purity is obtained.
  • this is then returned to the purification process, i.e. vaporized, optionally from a mixture with a solvent or diluent, and condensed by passing it into an organic solvent and crystallized from this.
  • the purification process described can also be carried out directly in the work-up of the extract phase by distillation of the TEDA leaving the column.
  • the process of the present invention allows the reuse of the solvent used in the crystallization of the TEDA and thus makes possible a reduction in the amount of fresh solvent required.
  • the work-up of the extract phase and the recycling of the TEDA which is made possible in this way also increases the yield of TEDA compared to the way in which the process has been carried out hitherto.
  • a solvent for example water
  • a carrier gas e.g. N 2 or Ar
  • the bottom product is pumped into a further distillation column having about 30 theoretical plates.
  • a temperature at the top of from 140 to 160° C. and a pressure of from 500 mbar to 1.5 bar, piperazine is separated off at the top of this column and is optionally fed back into the synthesis reactor.
  • the bottom product comprising TEDA and high boilers is pumped into a further distillation column having about 25 theoretical plates. At a pressure of from 500 mbar to 1.5 bar, the high boilers are discharged at the bottom of this column.
  • TEDA having a purity of >95% by weight, in particular >97% by weight, is taken off in vapor form via a partial condenser and is directly quenched in a solvent, preferably pentane and/or cyclohexane, at from 30 to 100° C., preferably from 30 to 60° C., in a falling film condenser and is dissolved at the same time (TEDA quench).
  • TEDA is crystallized from the solution in a crystallization step by vaporization of the solvent at from 10 to 100° C., preferably from 20 to 40° C., and a pressure of from 0.1 to 5 bar, preferably from 0.5 to 1.5 bar, or by cooling to a temperature of generally from ⁇ 10 to 40° C., preferably from 0 to 10° C.
  • the suspension taken off from the crystallizer is separated into high-purity TEDA and mother liquor in a solid/liquid separation, e.g. in a centrifuge.
  • the mother liquor, which still contains residual TEDA is then brought into intimate contact with an extractant, preferably water, at from 10 to 100° C., preferably from 20 to 40° C., and a pressure of from 0.1 to 5 bar, preferably from 0.5 to 1.5 bar, in an extraction step, for example in a mixer-settler or an extraction column.
  • an extractant preferably water
  • the extract phase leaving the extraction after mass transfer and phase separation which contains the major part of the TEDA and the undesirable by-products and decomposition products which lead to a reduction in the quality of the TEDA, is returned to the reactor or passed to a distillation.
  • the TEDA obtained after distillation can be returned to the purification stage.
  • the raffinate phase which contains only traces of TEDA, is returned to the TEDA quench.
  • the experiments were carried out in a 41 (catalyst volume) salt bath reactor (shell-and-tube reactor containing 7 tubes, internal diameter 21 mm, length 2 m) made of stainless steel and heated by means of electric heating tapes.
  • the pipes for the reactor feed, crude reaction product and the distillation section were partly configured as double-walled tubes and were oil-heated.
  • the components of the plant were protectively heated and were individually matched to the temperature required in each case by use of different heating circuits.
  • the catalyst used was a zeolite in the form of extrudates (diameter: about 2 mm, length: about 30 mm) (catalyst bed).
  • the feed had the following composition (figures in % by weight): Ethylenediamine 30% Piperazine 20% Water 50%.
  • the uncondensed material was, after a gas/liquid separator, conveyed to the distillation column.
  • the low boilers (ammonia, ethylamine, water) were taken off in liquid form at the top of the column at atmospheric pressure and a temperature at the top of 96° C.
  • the glass column having a diameter of 50 mm was equipped with 60 bubble cap trays.
  • the reflux ratio was about 10:1.
  • Piperazine was taken off in liquid form at the top of the column at atmospheric pressure and a temperature at the top of 150° C. and was recirculated to the reactor.
  • the bottom product from the distillation column was pumped continuously at 185° C. into the next distillation column.
  • the glass column having a diameter of 50 mm was equipped with 50 bubble cap trays.
  • the reflux ratio was about 8:1.
  • the high boilers were discharged continuously at 200° C. from the bottom of the column, and the temperature of the oil-heated vaporizer was 230° C.
  • crystalline TEDA was separated from the mother liquor on a suction filter. TEDA was obtained in a purity of at least 99.5% by weight.
  • the extract phase can be returned to the reactor and the raffinate phase can be recirculated together with the pentane obtained in the evaporative crystallization and 50 g/h of fresh pentane back to the TEDA quench.
  • the recirculation enables the amount of fresh pentane to be reduced by about 75% and likewise enables the TEDA loss resulting from the bleeding-off of mother liquor to be reduced by about 75%.
  • the extract phase can be returned to the reactor and the raffinate phase can be recirculated together with the pentane obtained in the evaporative crystallization and 50 g/h of fresh pentane back to the TEDA quench.
  • the recirculation enables the amount of fresh pentane to be reduced by about 75% and likewise enables the TEDA loss resulting from the bleeding-off of mother liquor to be reduced by about 75%.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Nitrogen Condensed Heterocyclic Rings (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

In a process for the purification of triethylenediamine (TEDA) in which TEDA is vaporized and the gaseous TEDA is passed into a liquid solvent and is subsequently crystallized from this, the mother liquor obtained after the TEDA has been crystallized is extracted with an extractant which is immiscible or only slightly miscible with the solvent of the mother liquor and in which TEDA is readily soluble, and the TEDA-depleted mother liquor obtained after extraction and/or the TEDA-enriched extractant which has been used for the extraction are/is returned to the process.

Description

  • The present invention relates to a process for working-up mother liquor obtained in the preparation of triethylenediamine (TEDA) which has been subjected to a particular purification process. This purification process comprises vaporizing TEDA, passing it in gaseous form into a liquid solvent and crystallizing the TEDA from the resulting solution. The mother liquor obtained after this crystallization step is then worked-up according to the present invention. [0001]
  • TEDA is an important catalyst for the production of polyurethane foams. TEDA is solid at room temperature. Various methods are known for its preparation and purification, including the methods disclosed in the following publications: [0002]
  • DT-A 24 42 929; U.S. Pat. No. 3,297,701; DE-A 36 34 258; DE-A 17 45 627; DE-A 37 18 395; EP-A 111 928; EP-A 382 055; EP-A 842 935, EP-A 842 936; EP-A 831 096; EP-A 952 152 and U.S. Pat. No. 5,741,906. [0003]
  • The processes known hitherto for preparing TEDA lead to formation of product mixtures which comprise TEDA together with water, by-products such as piperazine and high molecular weight compounds and any solvent which may have been used in the reaction. TEDA is usually separated from these mixtures by batchwise or continuous distillation or rectification and is normally purified in a subsequent step by crystallization or recrystallization. [0004]
  • TEDA is comparatively difficult to handle without deterioration of the quality, in particular in respect of color and color stability, odor and purity, occurring. [0005]
  • The known, customary applications generally require a very pure, odorless and pure white TEDA. The following applications disclose processes which are said to give an appropriate TEDA quality: [0006]
  • DT-A 26 11 069; DE-A 28 49 993 and JP-A 49 048 609. [0007]
  • A disadvantage of these processes is that they do not give TEDA of the desired quality. [0008]
  • The patent applications DE 199 33 850.7 of Jul. 23, 1999 and DE 199 62 455.0 of Dec. 22, 1999 by the Applicant relate to processes for preparing pure TEDA in which TEDA is vaporized and the gaseous TEDA is passed into a liquid solvent and the TEDA is crystallized from the solution. [0009]
  • The application DE 101 00 943.7 of Jan. 10, 2001 by the Applicant describes a process for preparing a solution of pure TEDA, which comprises vaporizing TEDA from a mixture comprising a solvent or a diluent which has a boiling point at atmospheric pressure in the range from 175 to 250° C. and passing the gaseous TEDA into a liquid solvent. Subsequent crystallization of the TEDA from the resulting solution gives pure TEDA of high quality. [0010]
  • After a solid/liquid separation of the crystalline TEDA from the solvent, a mother liquor comprising TEDA together with undesirable by-products and decomposition products is obtained in the last three processes. Owing to the impurities, the mother liquor cannot be reused in the process. Up to now, it has not been possible to work-up this mother liquor in such a way that it could be reused or the TEDA present in the mother liquor could be recovered at all. For this reason, the mother liquor was generally discarded. As a result, a large amount of solvent was necessary and the losses of TEDA remaining in the mother liquor were undesirably high. [0011]
  • It is an object of the present invention to provide a process for the recovery of TEDA which comprises vaporizing the TEDA used as starting material, passing the gaseous TEDA into a solvent and crystallizing the TEDA from the solution and which allows at least part of the solvents used to be recycled to the process and may also allow the yield of TEDA to be increased. [0012]
  • We have found that this object is achieved by a process for the purification of TEDA in which TEDA is vaporized and the gaseous TEDA is passed into a liquid solvent and is subsequently crystallized from this, wherein the mother liquor obtained after the TEDA has been crystallized is extracted with an extractant which is immiscible or only slightly miscible with the solvent of the mother liquor and in which TEDA is readily soluble, and the TEDA-depleted mother liquor obtained after extraction and/or the TEDA-enriched extractant which has been used for the extraction are/is returned to the process. [0013]
  • The first step of the process of the present invention comprises the reaction steps of the purification of TEDA as described in the applications DE 199 33 850.7, 199 62 455.0 and DE 101 00 943.7 by the Applicant. The processes for purifying TEDA described in these applications are an integral part of the process of the present application and are hereby incorporated by reference. The processes will be briefly described again below. [0014]
  • Passing the gaseous TEDA into a liquid solvent (TEDA quench) significantly reduces the formation of undesirable by-products which lead to a reduction in quality. [0015]
  • Many organic solvents are suitable for this TEDA quench. Examples include aliphatic, cyclic or acyclic hydrocarbons, in particular cyclic and acylic, branched or unbranched alkanes or alkane mixtures, for example n-pentane, i-pentane, cyclopentane, hexane, cyclohexane, heptane, octane and petroleum ether, chlorinated aliphatic hydrocarbons, in particular chlorinated alkanes, for example dichloromethane, trichloromethane, dichloro ethers and trichloro ethers, aromatic hydrocarbons, for example benzene, toluene and xylenes, chlorinated aromatic hydrocarbons, for example chlorobenzene, alcohols, for example methanol, ethanol, ethylene glycol, 1,4-butanediol and polyether alcohols, in particular polyalkylene glycols, for example diethylene glycol, dipropylene glycol, monethylene glycol and 1,4-butane diol, ketones, in particular aliphatic ketones, for example acetone, methyl ethyl ketone and diethyl ketone, aliphatic carboxylic esters, for example methyl acetate and ethyl acetate, aliphatic nitriles, for example acetonitrile and propionitrile, ethers, for example dioxane, THF, diethyl ether and ethylene glycol dimethyl ether and also mixtures of the solvents listed. [0016]
  • The solvent used for the TEDA quench is preferably an aliphatic hydrocarbon or a polyalkylene glycol, in particular a saturated cyclic or acyclic, aliphatic hydrocarbon having from 5 to 8 carbon atoms, for example pentane, hexane, cyclohexane or heptane, or dipropylene glycol. The crystallization of the pure TEDA from the TEDA solution prepared according to the present invention can be carried out by methods known to those skilled in the art. The TEDA crystals obtained by a subsequent, multistage or preferably single-stage crystallization are highly pure. [0017]
  • The gaseous TEDA is passed into the liquid solvent in a quenching apparatus, preferably a falling film condenser (thin film, trickle film or falling stream condenser) or in a nozzle apparatus. The gaseous TEDA can be conveyed in cocurrent or in countercurrent to the liquid solvent. It is advantageous to pass the gaseous TEDA into the quenching apparatus from above. Also advantageous is the tangential introduction of the liquid solvent at the top of the falling film condenser or introduction of the liquid solvent through one or more nozzles to achieve complete wetting of the inner wall of the quenching apparatus. [0018]
  • The amount of solvent used is chosen according to practical considerations. In general, the amount used is such that, depending on the type of solvent, solutions having a TEDA content of from about 1 to 50% by weight, preferably from 20 to 40% by weight, are obtained. [0019]
  • In general, the temperature in the TEDA quench is set to from 20 to 100° C., preferably from 30 to 60° C., by heating/cooling the solvent used and/or the quenching apparatus. [0020]
  • The absolute pressure in the TEDA quench is generally from 0.5 to 1.5 bar. [0021]
  • If, in the purification of the TEDA, the TEDA is, as described in DE 101 00 943.7, vaporized from a mixture with a solvent or diluent, the solvent or diluent preferably has a boiling point at atmospheric pressure of from 180 to 250° C., in particular from 180 to 230° C., especially from 190 to 210° C. [0022]
  • Particularly useful solvents or diluents which may be present in the mixture from which the TEDA is vaporized are inert [0023]
  • polar aprotic solvents such as alkyl-2-pyrrolidones, for example N-methyl-2-pyrrolidone (NMP), 1-ethyl-2-pyrrolidone, 1,5-dimethyl-2-pyrrolidone, 1-isopropyl-2-pyrrolidone, ethers, for example diethylene glycol diethyl ether, triethylene glycol dimethyl ether and triethylene glycol diethyl ether, ketones, for example acetophenone and propiophenone, lactones, for example γ-buyrolactone, sulfoxides, for example dimethyl sulfoxide, carboxylic esters, for example dimethyl fumarate, nitriles, for example benzonitrile, and ureas, for example 1,3-dimethylimidazolidin-2-one (DMEU) and tetramethylurea, [0024]
  • cyclic or acyclic hydrocarbons, in particular saturated cyclic or acyclic hydrocarbons, for example undecane, dodecane, cis-decalin and trans-decalin, [0025]
  • chlorinated aliphatic hydrocarbons, for example 1-chlorooctane and 1,1-dichlorooctane, [0026]
  • aromatic hydrocarbons, nitroaromatics and phenols, for example naphthalene, n-butylbenzene, phenol, cresol, nitrobenzene and nitrophenol, [0027]
  • chlorinated aromatic hydrocarbons, for example 1,2-dichlorobenzene, benzyl chloride, 1,2,3,4-tetramethylbenzene and 1,2,3,5-tetramethylbenzene, [0028]
  • alcohols, for example benzyl alcohol, 2-ethylhexanol, 1-octanol, i-decanol, 1,2-propanediol, 1,3-propanediol, ethylene glycol, diethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butanediol, 1,3-butanediol, 2,3-butanediol, 1,4-butanediol, neopentyl glycol, diethylene glycol monomethyl ether and dipropylene glycol, [0029]
  • primary, secondary and tertiary amines, for example tri-n-butylamine, benzylamine, aniline, N-ethylaniline, N,N-dimethylaniline and N,N-diethylaniline, [0030]
  • N-alkylamides, for example N-methylformamide and N-methylacetamide and mixtures thereof. [0031]
  • Particular preference is given to polar aprotic solvents or diluents having an E[0032] N T of from 0.1 to 0.6, in particular from 0.2 to 0.5, especially from 0.3 to 0.45.
  • (For the definition of E[0033] N T, see Ch. Reichardt, Solvents and solvent effects in organic chemistry, 2nd Edition, VCH 1988).
  • Very particularly preferred solvents are NMP and ethylene glycol. [0034]
  • The solvent or diluent present in the mixture from which the TEDA is vaporized is preferably added to the crude or still contaminated TEDA after the synthesis of the TEDA. [0035]
  • The solvent or diluent can be used in a single pass or as a circulating solution after removal of the high boilers. [0036]
  • The amount of solvent or diluent used is chosen according to practical considerations. In general, the amount used is such that, depending on the type of solvent or diluent, solutions or mixtures having a TEDA content of from about 1 to 90% by weight, preferably from 40 to 70% by weight, are obtained. [0037]
  • The vaporization of the TEDA, optionally from a mixture of this with a solvent or diluent, can be carried out by methods and under conditions with which those skilled in the art are familiar, e.g. in a distillation or rectification apparatus in which the TEDA is placed, optionally together with the solvent or diluent. [0038]
  • The gaseous TEDA is preferably obtained at the top or at a side offtake of a distillation column. The gaseous TEDA in the process of the present invention generally has a purity of greater than 90% by weight, preferably greater than 95% by weight, in particular greater than 97% by weight. [0039]
  • If a mixture comprising TEDA and the solvent or diluent from which the TEDA is vaporized according to the present invention (e.g. the bottoms from the TEDA distillation column) is used, the temperature of the mixture is set to ≦230° C., preferably from 190 to 210° C., by selection of the solvent or diluent to be used, the TEDA content of the mixture and/or the pressure. The absolute pressure is generally from 0.1 to 5 bar, preferably from 0.5 to 1.5 bar. [0040]
  • The time between when the gaseous TEDA used in the process of the present invention is obtained and the TEDA quench is advantageously ≦10 seconds. [0041]
  • The TEDA to be purified can be obtained by known methods, e.g. by reaction of monoethanolamine, diethanolamine, triethanolamine, ethylenediamine, diethylenetriamine, triethylenetetramine, piperazine, N-(2-hydroxyethyl)piperazine, N,N′-bis(2-hydroxyethyl)piperazine, N-(2-aminoethyl)piperazine, N,N′-bis(2-aminoethyl)piperazine, morpholine, or mixtures thereof over a catalyst, for example metal pyrophosphates, metal phosphates, e.g. alkaline earth metal monohydrogen phosphate, zeolites, zirconium phosphates, Al[0042] 2O3, SiO2, phosphorus-containing TiO2 or ZrO2, at elevated temperature, generally from 250 to 450° C. The pressure is usually from 0.1 to 50 bar, in particular from 0.1 to 5 bar. The reaction can optionally be carried out in the presence of an inert polar aprotic solvent such as an N-alkylpyrrolidone, for example N-methylpyrrolidone, dioxane, THF, a dialkylformamide, for example dimethylformamide, a dialkylacetamide, for example dimethylacetamide, or an inert polar protic solvent, for example water, and an inert carrier gas, for example N2 or Ar.
  • The TEDA is subsequently crystallized from the mother liquor and separated off by solid/liquid separation. The mother liquor obtained in this way is, according to the present invention, brought into intimate contact with an extractant in an extraction step. Mass transfer takes place in this step. The extractant is selected so that the TEDA is taken up by it. The by-products and decomposition products responsible for the reduction in the quality of the TEDA are likewise dissolved in the extractant. The mother liquor is thereby freed of these by-products and decomposition products and can be returned to the process. [0043]
  • After mass transfer is complete, the mother liquor which has been depleted in TEDA, by-products and decomposition products (raffinate phase) and the extractant which has been enriched in TEDA (extract phase) are separated. [0044]
  • The solvent used as extractant advantageously has the following properties: [0045]
  • The extractant should have a large miscibility gap with the solvent used in the crystallization step; the mutual solubility of extractant and solvent should be <10% by weight, preferably <1% by weight. TEDA should dissolve significantly better in the extractant than in the solvent which is used in the crystallization step. Furthermore, the extractant and the solvent used in the crystallization step should have a sufficient density difference. This aids separation of the extract phase and the raffinate phase. The density difference should preferably be >50 kg/m[0046] 3, in particular>100 kg/m3.
  • Solvents which are preferred according to the present invention as extractants are water and water-miscible solvents such as lower alcohols or dihydric or polyhydric alcohols. Examples of suitable alcohols include methanol, ethanol, n-propanol, i-propanol, ethylene glycol, polyethylene glycol and glycerol. The alcohols can be used individually or as mixtures, optionally also in admixture with water. The most preferred extractant is water. [0047]
  • Since not only the TEDA but also the by-products and decomposition products formed in its synthesis and purification go into the extract phase during the extraction, this extraction gives a mother liquor (raffinate phase) which is free of TEDA and the undesirable by-products. The mother liquor can be recycled and reused as organic solvent into which gaseous TEDA is passed and from which it is subsequently crystallized. Such recycling is not possible in the case of a mother liquor which has not been worked up according to the present invention, since the impurities present in the mother liquor reduce the quality of the TEDA obtained. [0048]
  • The work-up according to the present invention of the mother liquor by means of an extractant can be carried out by the methods and under the conditions with which those skilled in the art are familiar, e.g. in an extraction apparatus into which the mother liquor is introduced continuously or batchwise, in each case together with the extractant. [0049]
  • The extraction according to the present invention reduces the amount of TEDA present in the mother liquor to values of <10% by weight, preferably <1% by weight, of the original value. The extract phase after the extraction according to the present invention accordingly contains >90% by weight, preferably >99% by weight, of the TEDA originally present in the mother liquor. Depending on the type of extractant used, solutions having a TEDA content of from about 1 to 40% by weight, preferably from 5 to 30% by weight, in particular 10-30% by weight, are obtained. [0050]
  • The extract phase, too, may if appropriate be recycled after the extraction according to the present invention has been carried out and be reused for the extraction. The degree of saturation of TEDA and by-products and intermediates in the extract phase will determine whether and how often the extract phase can be reused. Of course, the degree of saturation depends greatly on the nature of the solvent used as extractant and on the solubility of TEDA and the by-products and intermediates in this solvent. However, the extractant can also be taken from the process and worked up after a single extraction. This is done, in particular, when using water because of its ready availability. [0051]
  • When a certain degree of saturation has been reached, the solvent used for the extraction can no longer take up TEDA and by-product and can no longer be recirculated. This extract phase is then worked up and separated into the solvent used and TEDA, preferably by distillation. The solvent is then reused as extractant. Depending on the type and manner of work-up, TEDA of differing purity is obtained. In general, this is then returned to the purification process, i.e. vaporized, optionally from a mixture with a solvent or diluent, and condensed by passing it into an organic solvent and crystallized from this. The purification process described can also be carried out directly in the work-up of the extract phase by distillation of the TEDA leaving the column. [0052]
  • The process of the present invention allows the reuse of the solvent used in the crystallization of the TEDA and thus makes possible a reduction in the amount of fresh solvent required. The work-up of the extract phase and the recycling of the TEDA which is made possible in this way also increases the yield of TEDA compared to the way in which the process has been carried out hitherto. [0053]
  • In a preferred embodiment, the process of the present invention can be carried out as follows: [0054]
  • A TEDA-containing mixture which has been obtained, for example, as crude reaction product from a continuous process in which ethylenediamine and piperazine are reacted in a gas-phase reactor at from 320 to 420° C. and from 0.5 to 1.5 bar in the presence of a solvent (for example water), a carrier gas (e.g. N[0055] 2 or Ar) and a zeolite catalyst is fed into a distillation apparatus comprising a distillation column having about 15 theoretical plates. In this column, low boilers (for example ammonia, ethylamine, water) are separated off at a temperature at the top of from 95 to 120° C. and a pressure of generally from 500 mbar to 1.5 bar. The bottom product is pumped into a further distillation column having about 30 theoretical plates. At a temperature at the top of from 140 to 160° C. and a pressure of from 500 mbar to 1.5 bar, piperazine is separated off at the top of this column and is optionally fed back into the synthesis reactor.
  • The bottom product comprising TEDA and high boilers is pumped into a further distillation column having about 25 theoretical plates. At a pressure of from 500 mbar to 1.5 bar, the high boilers are discharged at the bottom of this column. At the top of the column, TEDA having a purity of >95% by weight, in particular >97% by weight, is taken off in vapor form via a partial condenser and is directly quenched in a solvent, preferably pentane and/or cyclohexane, at from 30 to 100° C., preferably from 30 to 60° C., in a falling film condenser and is dissolved at the same time (TEDA quench). [0056]
  • After the TEDA quench, TEDA is crystallized from the solution in a crystallization step by vaporization of the solvent at from 10 to 100° C., preferably from 20 to 40° C., and a pressure of from 0.1 to 5 bar, preferably from 0.5 to 1.5 bar, or by cooling to a temperature of generally from −10 to 40° C., preferably from 0 to 10° C. [0057]
  • The suspension taken off from the crystallizer is separated into high-purity TEDA and mother liquor in a solid/liquid separation, e.g. in a centrifuge. The mother liquor, which still contains residual TEDA, is then brought into intimate contact with an extractant, preferably water, at from 10 to 100° C., preferably from 20 to 40° C., and a pressure of from 0.1 to 5 bar, preferably from 0.5 to 1.5 bar, in an extraction step, for example in a mixer-settler or an extraction column. [0058]
  • The extract phase leaving the extraction after mass transfer and phase separation, which contains the major part of the TEDA and the undesirable by-products and decomposition products which lead to a reduction in the quality of the TEDA, is returned to the reactor or passed to a distillation. The TEDA obtained after distillation can be returned to the purification stage. The raffinate phase, which contains only traces of TEDA, is returned to the TEDA quench. [0059]
  • The invention is illustrated by the following examples. [0060]
    • EXAMPLES Example 1 Comparative Example
  • The experiments were carried out in a 41 (catalyst volume) salt bath reactor (shell-and-tube reactor containing 7 tubes, internal diameter 21 mm, length 2 m) made of stainless steel and heated by means of electric heating tapes. The pipes for the reactor feed, crude reaction product and the distillation section were partly configured as double-walled tubes and were oil-heated. The components of the plant were protectively heated and were individually matched to the temperature required in each case by use of different heating circuits. The catalyst used was a zeolite in the form of extrudates (diameter: about 2 mm, length: about 30 mm) (catalyst bed). [0061]
  • The feed of 1300 g/h together with 3 standard l/h (standard l=standard liters=volume at STP) of nitrogen were introduced at atmospheric pressure into the salt bath reactor heated to 350° C. (WHSV over the catalyst: 1 kg of feed per l of cat. (bed volume) and per h). [0062]
  • The feed had the following composition (figures in % by weight): [0063]
    Ethylenediamine 30%
    Piperazine 20%
    Water  50%.
  • The gaseous reaction product was condensed at 80° C. in a quench using circulated liquid which consisted of liquid reaction product which had been obtained previously (=reaction product quench). [0064]
  • Analysis of the condensate indicated the following composition (figures in % by weight): [0065]
    Ammonia  3%
    Piperazine 17%
    Triethylenediamine 23%
    Water 54%
    Remainder high boilers and other by -
    products.
  • The uncondensed material was, after a gas/liquid separator, conveyed to the distillation column. [0066]
  • Part of the liquid reaction product was cooled and used as circulated liquid (for the reaction product quench), while another part was pumped continuously to a distillation column by means of a pump. The glass column having a diameter of 50 mm was equipped with 30 bubble cap trays. The reflux ratio was about 1:1. [0067]
  • The low boilers (ammonia, ethylamine, water) were taken off in liquid form at the top of the column at atmospheric pressure and a temperature at the top of 96° C. [0068]
  • The bottom product from the distillation column was pumped continuously at 155° C. into a downstream distillation column. [0069]
  • The glass column having a diameter of 50 mm was equipped with 60 bubble cap trays. The reflux ratio was about 10:1. Piperazine was taken off in liquid form at the top of the column at atmospheric pressure and a temperature at the top of 150° C. and was recirculated to the reactor. [0070]
  • 200 g/h of N-methyl-2-pyrrolidone were fed into the bottom of the column. [0071]
  • Analysis of the bottom product indicated the following composition (figures in % by weight): [0072]
    Piperazine 0.03%
    Triethylenediamine   53%
    N-methyl-2-pyrrolidone   43%
    Remainder high boilers and other by -
    products.
  • The bottom product from the distillation column was pumped continuously at 185° C. into the next distillation column. The glass column having a diameter of 50 mm was equipped with 50 bubble cap trays. The reflux ratio was about 8:1. The high boilers were discharged continuously at 200° C. from the bottom of the column, and the temperature of the oil-heated vaporizer was 230° C. At the top of the column, TEDA was taken off in vapor form and quenched at about 30° C. in pentane as solvent (mixture of 80% by weight of n-pentane and 20% by weight of isopentane) and simultaneously dissolved (=TEDA quench). For the TEDA quench, use was made of a falling film condenser (trickle film condenser or falling stream condenser) into which gaseous TEDA was introduced from the top. Pentane was fed in tangentially at the top of the falling film condenser. The resulting solution had the following composition (figures in % by weight): [0073]
    Pentane   94%
    Piperazine 0.01%
    Triethylenediamine   5%
    Remainder by-products.
  • After the partial removal of pentane by evaporative crystallization at 25° C. and a pressure of 570 mbar, crystalline TEDA was separated from the mother liquor on a suction filter. TEDA was obtained in a purity of at least 99.5% by weight. [0074]
  • Part of the mother liquor was recirculated together with the pentane obtained in the evaporative crystallization and 200 g/h of fresh pentane back to the TEDA quench. To prevent accumulation of undesirable by-products and decomposition products which lead to a reduction in the quality of the TEDA, about 200 g/h of mother liquor were bled off from the circuit. [0075]
  • Analysis of the mother liquor bled off indicated the following composition (figures in % by weight): [0076]
    Pentane   95%
    Piperazine 0.02%
    Triethylenediamine  4.7%
    Remainder by-products.
    • Example 2 According to the Present Invention
  • The experiment was carried out as described in example 1, but the mother liquor was mixed with water in a ratio of about 1:1, shaken and, after separation of the phases, analyzed. [0077]
  • Analysis of the extract phase indicated the following composition (figures in % by weight): [0078]
    Pentane <0.01%
    Piperazine 0.02%
    Triethylenediamine 4.4%
    Water 95.5%
    Remainder by-products.
  • Analysis of the raffinate phase indicated the following composition (figures in % by weight): [0079]
    Pentane 99.95%
    Piperazine <0.001%
    Triethylenediamine 0.02%
    Water 0.02%
    Remainder by-products.
  • The extract phase can be returned to the reactor and the raffinate phase can be recirculated together with the pentane obtained in the evaporative crystallization and 50 g/h of fresh pentane back to the TEDA quench. [0080]
  • The recirculation enables the amount of fresh pentane to be reduced by about 75% and likewise enables the TEDA loss resulting from the bleeding-off of mother liquor to be reduced by about 75%. [0081]
    • Example 3 According to the Present Invention
  • The experiment was carried out as described in example 1, but the mother liquor was mixed with water in a ratio of about 1:4, shaken and, after separation of the phases, analyzed. [0082]
  • Analysis of the extract phase indicated the following composition (figures in % by weight): [0083]
    Pentane <0.01%
    Piperazine 0.2%
    Triethylenediamine 23.6%
    Water 71.7%
    Remainder by-products.
  • Analysis of the raffinate phase indicated the following composition (figures in % by weight): [0084]
    Pentane 99.92%
    Piperazine >0.001%
    Triethylenediamine 0.04%
    Water 0.01%
    Remainder by-products.
  • The extract phase can be returned to the reactor and the raffinate phase can be recirculated together with the pentane obtained in the evaporative crystallization and 50 g/h of fresh pentane back to the TEDA quench. [0085]
  • The recirculation enables the amount of fresh pentane to be reduced by about 75% and likewise enables the TEDA loss resulting from the bleeding-off of mother liquor to be reduced by about 75%. [0086]

Claims (17)

We claim:
1. A process for the purification of triethylenediamine (TEDA) in which TEDA is vaporized and the gaseous TEDA is passed into a liquid solvent and is subsequently crystallized from this, wherein the mother liquor obtained after the TEDA has been crystallized is extracted with an extractant which is immiscible or only slightly miscible with the solvent of the mother liquor and in which TEDA is readily soluble, and the TEDA-depleted mother liquor obtained after extraction and/or the TEDA-enriched extractant which has been used for the extraction are/is returned to the process.
2. A process as claimed in claim 1, wherein the TEDA is vaporized from a mixture comprising a diluent or solvent which has a boiling point at atmospheric pressure of from 175 to 250° C. before being passed into the liquid solvent.
3. A process as claimed in claim 1, wherein the mutual solubility of the extractant and the solvent used in the crystallization step is <10% by weight.
4. A process as claimed in claim 3, wherein the mutual solubility is <1% by weight.
5. A process as claimed in claim 1, wherein the density difference between the extractant and the solvent used in the crystallization step is >50 kg/m3.
6. A process as claimed in claim 5, wherein the density difference is >100 kg/m3.
7. A process as claimed in claim 1, wherein the extractant is selected from the group consisting of water, lower alcohols and dihydric and polyhydric alcohols, preferably water, methanol, ethanol, n-propanol, i-propanol, ethylene glycol, polyethylene glycol, glycerol and mixtures thereof.
8. The process as claimed in claim 7, wherein the extractant is water.
9. A process as claimed in claim 1, wherein the solvent used in the crystallization step is selected from the group consisting of cyclic and acyclic hydrocarbons, chlorinated aliphatic hydrocarbons, aromatic hydrocarbons, alcohols, ketones, aliphatic carboxylic acids, aliphatic nitrites and esters.
10. The process as claimed in claim 9, wherein the solvent is pentane and/or dipropylene glycol.
11. A process as claimed in claim 1, wherein the extraction is carried out so that the amount of TEDA present in the mother liquor is reduced to <10% by weight.
12. The process as claimed in claim 11, wherein the amount of mother liquor is reduced to <1% by weight.
13. A process as claimed in claim 1, wherein the TEDA-enriched extractant is worked up.
14. A process as claimed in claim 13, wherein the extractant is worked up by distillation.
15. A process as claimed in claim 13, wherein the TEDA obtained after the work-up is returned to the purification step.
16. A process as claimed in claim 1, wherein the extraction of the mother liquor is carried out continuously or batchwise.
17. A process as claimed in claim 16, wherein the extraction is carried out in an extraction apparatus.
US10/138,337 2001-05-10 2002-05-06 Work-up of the mother liquor obtained in the preparation of high-purity triethylenediamine Expired - Fee Related US7345173B2 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10122502 2001-05-10
DE10122502A DE10122502A1 (en) 2001-05-10 2001-05-10 Purification of triethylene diamine, useful as a catalyst for the production of polyurethane foam, comprises crystallization and extraction of the resulting mother liquor with an extraction agent
DE10122502.4 2001-05-10

Publications (2)

Publication Number Publication Date
US20030004349A1 true US20030004349A1 (en) 2003-01-02
US7345173B2 US7345173B2 (en) 2008-03-18

Family

ID=7684141

Family Applications (1)

Application Number Title Priority Date Filing Date
US10/138,337 Expired - Fee Related US7345173B2 (en) 2001-05-10 2002-05-06 Work-up of the mother liquor obtained in the preparation of high-purity triethylenediamine

Country Status (8)

Country Link
US (1) US7345173B2 (en)
EP (1) EP1258485B1 (en)
JP (1) JP2002363181A (en)
KR (1) KR20020086267A (en)
CN (1) CN1266153C (en)
AT (1) ATE298340T1 (en)
DE (2) DE10122502A1 (en)
ES (1) ES2243619T3 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080021218A1 (en) * 2004-05-15 2008-01-24 Basf Aktiengesellschaft Method for Producing a Solution of Pure Triethylenediamine (Teda)
US20080312439A1 (en) * 2005-12-23 2008-12-18 Basf Aktiengesellschaft Work-Up in the Preparation of High-Purity Triethylenediamine

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10303696A1 (en) * 2003-01-30 2004-08-12 Basf Ag Decolorization and color stabilization of TEDA solution
DE102009027791B4 (en) 2009-07-17 2013-02-21 Basf Se Composition containing triethylenediamine, monethyleneglycol and borohydride
CN102030755B (en) * 2010-11-24 2012-05-30 西安近代化学研究所 Method for preparing high-purity triethylene diamine
CN103664964B (en) * 2013-12-18 2016-03-02 西安近代化学研究所 The absorption process of triethylene diamine production rectifying gas and device

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6627756B1 (en) * 1999-07-23 2003-09-30 Basf Aktiengesellschaft Preparation of pure triethylenediamine

Family Cites Families (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3123607A (en) 1964-03-03 Recovery of diazabicyclo-octane
US902073A (en) 1908-08-12 1908-10-27 Charles H Gueritey Amusement apparatus.
US2937176A (en) 1956-12-17 1960-05-17 Houdry Process Corp Preparation of diazabicyclo-octane
GB902073A (en) 1958-05-09 1962-07-25 Houdry Process Corp Separation and purification of triethylene diamine
DE1745627B1 (en) 1958-05-24 1970-05-14 Air Prod & Chem Process for the preparation of 1,4-diazabicyclo-2,2,2-octane and piperazine
US3297701A (en) 1962-03-23 1967-01-10 Jefferson Chem Co Inc Synthesis of diazabicyclo-(2, 2, 2)-octane and derivatives
US3400129A (en) * 1965-10-15 1968-09-03 Jefferson Chem Co Inc Purification of 2-methyltriethylenediamine by solvent extraction and azeotropic distillation
JPS4948609A (en) 1972-09-13 1974-05-11
DE2442929C3 (en) 1974-09-07 1978-07-06 Basf Ag, 6700 Ludwigshafen Process for the preparation of 1,4-diazabicyclo [2,2,2 square brackets to octane
US3993651A (en) 1975-03-17 1976-11-23 Texaco Development Corporation Triethylenediamine recovery
JPS6036439B2 (en) 1977-11-22 1985-08-20 東ソー株式会社 Separation and recovery method for triethylenediamine
US4182864A (en) 1978-09-21 1980-01-08 Texaco Development Corporation Triethylenediamine process
DE2846813A1 (en) 1978-10-27 1980-05-08 Bayer Ag METHOD FOR PRODUCING 1,4-DIAZABICYCLO- (2,2,2) -OCTANE
US4233447A (en) 1978-12-21 1980-11-11 Texaco Development Corp. Process for purifying triethylenediamine
GB2080283B (en) 1980-07-15 1984-04-18 Texaco Development Corp Process for purifying triethylenediamine
EP0111928A1 (en) 1982-12-20 1984-06-27 Air Products And Chemicals, Inc. Catalysis of condensation reactions
US4757143A (en) 1986-06-09 1988-07-12 Texaco Inc. Catalytic method for the manufacture of triethylenediamine
US4804758A (en) 1986-10-08 1989-02-14 Basf Aktiengesellschaft Preparation of 1,4-diazabicyclo[2.2.2]octanes
DE3634258A1 (en) 1986-10-08 1988-04-21 Basf Ag Process for the preparation of 1,4-diazabicyclo[2.2.2]octanes
DE3903622A1 (en) 1989-02-08 1990-08-09 Basf Ag METHOD FOR PRODUCING 1,4-DIAZABICYCLO-2,2,2-OCTANE
US5756741A (en) 1996-11-15 1998-05-26 Air Products And Chemicals, Inc. Process for the production of triethylenediamine
US5741906A (en) 1996-11-15 1998-04-21 Air Products And Chemicals, Inc. Production of triethylenediamine using surface acidity deactivated zeolite catalysts
DE19962455A1 (en) 1999-12-22 2001-06-28 Basf Ag Preparation of pure triethylenediamine solution and crystals, useful as catalyst for polyurethane foam production, comprises vaporization, passing vapor into liquid solvent and crystallization from solution
DE19933850A1 (en) 1999-07-23 2001-01-25 Basf Ag Preparation of pure triethylenediamine solution and crystals, useful as catalyst for polyurethane foam production, comprises vaporization, passing vapor into liquid solvent and crystallization from solution
DE10100943A1 (en) 2001-01-10 2002-07-11 Basf Ag Production of a solution of pure triethylenediamine comprises evaporation from a mixture comprising a solvent or a diluent having a specified boiling point at normal pressure
DE10145117A1 (en) 2001-09-13 2003-04-03 Basf Ag Process for the preparation of high-purity triethylenediamine by introducing the triethylenediamine into a solvent after the high boilers have been separated off beforehand

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6627756B1 (en) * 1999-07-23 2003-09-30 Basf Aktiengesellschaft Preparation of pure triethylenediamine

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080021218A1 (en) * 2004-05-15 2008-01-24 Basf Aktiengesellschaft Method for Producing a Solution of Pure Triethylenediamine (Teda)
US7872131B2 (en) 2004-05-15 2011-01-18 Basf Se Method for producing a solution of pure triethylenediamine (TEDA)
US20080312439A1 (en) * 2005-12-23 2008-12-18 Basf Aktiengesellschaft Work-Up in the Preparation of High-Purity Triethylenediamine

Also Published As

Publication number Publication date
EP1258485B1 (en) 2005-06-22
DE50203442D1 (en) 2005-07-28
CN1266153C (en) 2006-07-26
EP1258485A1 (en) 2002-11-20
ES2243619T3 (en) 2005-12-01
US7345173B2 (en) 2008-03-18
KR20020086267A (en) 2002-11-18
DE10122502A1 (en) 2002-11-14
ATE298340T1 (en) 2005-07-15
JP2002363181A (en) 2002-12-18
CN1385430A (en) 2002-12-18

Similar Documents

Publication Publication Date Title
US6552194B2 (en) Process for the preparation of pure triethylenediamine (TEDA)
US7345173B2 (en) Work-up of the mother liquor obtained in the preparation of high-purity triethylenediamine
US6627756B1 (en) Preparation of pure triethylenediamine
US7872131B2 (en) Method for producing a solution of pure triethylenediamine (TEDA)
JP4436673B2 (en) Process for producing high purity triethylenediamine
US7074926B2 (en) Decoloration and color stabilization of TEDA solution
US20080312439A1 (en) Work-Up in the Preparation of High-Purity Triethylenediamine

Legal Events

Date Code Title Description
AS Assignment

Owner name: BASF AKTIENGESELLSCHAFT, GERMANY

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:LANG, ORTMUND;FUNHOFF, DIRK;RUMPF, BERND;AND OTHERS;REEL/FRAME:012866/0538

Effective date: 20020225

AS Assignment

Owner name: BASF SE, GERMANY

Free format text: CHANGE OF NAME;ASSIGNOR:BASF AKTIENGESELLSCHAFT;REEL/FRAME:020519/0594

Effective date: 20080114

STCF Information on status: patent grant

Free format text: PATENTED CASE

FPAY Fee payment

Year of fee payment: 4

FPAY Fee payment

Year of fee payment: 8

FEPP Fee payment procedure

Free format text: MAINTENANCE FEE REMINDER MAILED (ORIGINAL EVENT CODE: REM.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

LAPS Lapse for failure to pay maintenance fees

Free format text: PATENT EXPIRED FOR FAILURE TO PAY MAINTENANCE FEES (ORIGINAL EVENT CODE: EXP.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

STCH Information on status: patent discontinuation

Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362

FP Lapsed due to failure to pay maintenance fee

Effective date: 20200318